William has been the Director General of the Guernsey Financial Services Commission since 2013. He served on the Executive Committee of the International Association of Insurance Supervisors (IAIS) between 2014 and 2022 where he chaired both the Audit and Risk Committee and the Standards Assessment Working Group, establishing IAIS's regulatory assessment programme. He has a strong interest in Supervisory Technology and Green Finance. Under his leadership, the Commission has developed:
- the Guernsey Green Fund framework (2018) and the Natural Capital Fund framework (2022), both possibly global firsts in environmental finance;
- bought into force environmentally sensitive green capital rules for life insurers - possibly another world first for insurance regulation; and
- made moves, including planting 53,000 trees in 2022 in an ecologically advantageous fashion, towards becoming a net zero regulator.
Prior to becoming a financial regulator, William worked at the UK Cabinet Office where he helped write "Regulation - Less is More, a report to the Prime Minister". His other publications include: "Freedom for Public Services; The Costs of Regulation and PRISM Explained - Implementing Risk Based Supervision". Earlier in his career, William gained private sector experience working for an international energy firm on three continents and a US strategy house, Monitor Group. He also served as a volunteer police office in London, a school governor in a deprived neighbourhood as well as being a parish and district councillor.
From 2006 to 2010, he supervised large insurers and investment firms at the UK FSA where he was also asked to lead an emergency credit institutions team during the Global Financial Crisis. In 2010, he moved to become Head of Risk at the Central Bank of Ireland where he reinvented Irish financial services supervisory processes as it recovered from the Euro crisis before playing an influential role in the operational design of the European Central Bank's banking union with it then adopting the software he designed to implement its supervisory operating model.